Design

Configuration

1. First we need to register GW and the video endpoint to the GK, we can run GK feature on the same router if we have IOS with GK feature for example - C2800NM-IPVOICE_IVS-M.
The most simple setup will be if we register endpoing with full E164 number and GW with the tech prefix, chousen in a way it will allow dialing to PSTN without any number transformation.
Assume PSTN will requre 00 for international call, in this case we can use the following config on GK:

There is no need to configure zone prefixes as GW will register with the tech prefix.
And VT will register with the full E164 number, so GK will always be able to resolve the them to IP.
For VT we need to allow direct calls to / from H.323 GW, so we disabling proxy requirement.

6. Now we can proceed with the preparation for the dial-peer config, first let define the codecs we will use on IP side.
Please keep in mind that GW will actually do the filtering of the codes it will announce to the endpoints on both sides.

7. This part is required to accept the incoming video calls, we need to have to provide the secondary numbers to the calling party, so they can call us on that numbers to add more bandwidth to the video call, that numbers will be sent out during ISO 13871 bonding stage.

!

voice class called number pool 3151
index 1 315140 - 315149

8. Now we need to apply that pool to the voice port to activate it:

!

voice-port 1/0:15
voice-class called-number-pool 3151

!

9. Now we are ready to proceed with the dial-peer configuration we need 4 of them, two incoming and two outgoing.
It is possible to use one POTS dial-peer as incoming and outgoing at the same time, but we will provide config for two of them for the sake of clarity: